Coherence resonance in a premixed combustor driven by a turbulence-induced color noise

Self-excited thermoacoustic oscillations occur in many propulsion systems, such as gas turbines and rocket motors. They are unwanted in these systems due to the detrimental outcomes, which includes the structure vibrations and enhanced thermal load to the combustor wall. Due to the complexity of the operating conditions and combustors' structure, considering the random noisy forcing on the combustion process will be more deeper and accurate to understand the stochastic behaviors of the practical combustion. In the present paper, the effects of turbulence-induced colored noise on the coherence motion of the combustion are theoretically and numerically studied. The resonance-like behavior in signal-to-noise ratio (SNR) is a manifestation of coherence resonance, and it is observed as either the noise intensity or the correlation time of the colored noise is varied. In addition, when the combustion system is closer to instability, SNR becomes larger and more distinguished.